Popular spit-in-a-tube genetics-testing companies like Ancestry
and 23andMe can - and frequently do -
sell your data to drugmakers. But on Wednesday, one of those
partnerships became much more explicit, when the pharmaceutical
giant GlaxoSmithKline announced it was acquiring a $300 million
stake in 23andMe.

As part of a
four-year deal between the two companies, GlaxoSmithKline
will comb
23andMe's genetic data to look for potential new drugs to
develop, also referred to as drug targets. It will also use the
genetic data to inform how patients are selected for clinical
trials.

If that news has you thinking about
how your own genetic material is being used for research,
know that though the DNA you submit to these services is
ostensibly anonymized, leaks can happen, and privacy advocates
note that such incidents could allow your data to find its way
elsewhere, perhaps without your knowledge.

Deleting your genetic data from these platforms can be a
surprisingly tricky process. Here's how to navigate removing your
spit sample and DNA data from the databases maintained by
23andMe, Ancestry, and Helix.

23andMe may keep your spit and data for up to a decade

23andMe Instagram

The core
service provided by most commercial genetic tests is built on the
extraction of your DNA from your spit - that's how you get the
information about your health or ancestry.

After registering your spit sample online with 23andMe, you will be asked whether
you'd like your saliva to be stored or discarded. But you are not
asked the same question about your raw genetic data, the DNA
extracted from your spit.

"By choosing to have 23andMe store either your saliva
sample or DNA extracted from your saliva, you are
consenting to having 23andMe and its contractors access and
analyze your stored sample, using the same or more advanced
technologies."

That leaves a bit of a gray area as far as what 23andMe has the
ability to keep and how it can use your DNA information. If your
spit or DNA sample is stored, the company can hold onto it for
one to 10 years, "unless we notify you otherwise," the document
says.

Still, you can submit a request that the company discard your
spit or close your account. To find instructions to do so,
go to its
customer-care page, navigate to "accounts and registration,"
scroll to the bottom of the bulleted list of options under
"account creation and access," and select the last one,
"requesting account closure."

If you want to
delete your DNA test results with Ancestry, use the navigation bar
at the top of the homepage to select "DNA." On the page with your
name at the top, scroll to the upper right corner, select
"settings," then go to "delete test results" on the column on the
right side.

The company's latest
privacy statement says that doing this will result in
Ancestry deleting the following within 30 days: "all genetic
information, including any derivative genetic information
(ethnicity estimates, genetic relative matches, etc.) from our
production, development, analytics, and research systems."

However, it says that if you opted into Ancestry's "informed
consent to research" when you signed up, the company cannot wipe
your genetic information from any "active or completed research
projects." But it will prevent your DNA from being used for new
research.